VANCOUVER -- The most powerful diagnostic technology to detect cancer and optimize the management of cancer patients is revolutionizing cancer care in the United States, western Europe and other nations. But it can't seem to gain a foothold in Canada, even though cancer is our leading cause of premature death.
The technology is PET (positron emission tomography) imaging, and it is uniquely able to detect active cancer cells before they create a mass that can then be identified by a CT or MRI scan. Because PET detects cancer at an earlier stage, the patient receives more timely treatment and has a greater probability of success.
Canadians need access to PET because large studies have shown it changes patient management plans in 36.5 per cent to 50 per cent of cases. That means a PET scan changes the doctor's treatment strategy in one-third to one-half of all cases, and this holds true for all cancer types. It also suggests doctors who don't utilize PET may be prescribing a suboptimal (or even wrong) treatment path for many patients.
Other studies show a PET scan eliminates the need for surgical biopsy in 70 per cent of cases and further procedures in up to 90 per cent of cases. It appears PET could provide a cost savings to our health-care system if used as a first-line diagnostic tool. Unfortunately, when Canadian doctors request a PET scan, it is most often as a last resort to diagnose a troublesome case.
If PET is so essential to determining the most appropriate treatment strategy, why are so many cancer patients unaware of it? Why aren't cancer groups advocating for its greater use? And why do so few doctors understand its clinical benefits?
A recently-released, groundbreaking report on the status of PET imaging in cancer care across Canada demonstrates that we lag far (embarrassingly far) behind the rest of the world in the adoption of PET. Further, it states that access to PET is dependent on what province you call home. In most provinces, PET is absent, difficult to access or relatively underutilized in cancer care.
The one exception is Quebec, where PET is an integral part of cancer care. Quebec has a well-functioning network of 13 PET scanners and carries out more than half of all PET scans in Canada. A PET scan is often the first diagnostic tool used when cancer is suspected, and thoracic/oncologic surgeons won't operate until they have seen a PET scan. If a PET scan changes treatment regimes in up to one-half of cases, there is a clear implication that Quebec cancer patients have a different standard of care than their counterparts in other provinces.
In Manitoba, there is one PET scanner, located at the Winnipeg Health Sciences Centre, and it carried out approximately 1,300 scans in both 2009 and 2010. It has the capacity to perform 2,000 scans, but the demand isn't there. This suggests doctors haven't adopted PET as part of their cancer-care protocols and aren't sending cancer patients for scans.
This reluctance often stems from doctors (both specialists and GPs) having to manage cancer for so long in PET-free environments; they see no need for another diagnostic tool because they don't know about the unique benefits of PET to patient management. There is very little medical education on PET and far too many doctors are a decade behind science in that they view PET as research, not clinical, technology. I've personally (and recently) dealt with oncologists who don't know the difference between a PET and a CT scan. Such experiences are rather discouraging when advocating for the best cancer care for a relative or friend.
Manitoba's PET services are also somewhat restricted in that the scanner is located in Winnipeg, a large population centre. Patients from the province's vast rural areas often don't have the strength, means or will to travel a long distance for a diagnostic procedure. This problem is common to many provinces.
That said, PET is not a miracle tool and changes in patient management don't always improve patient survival. Many times PET reveals cancer to be at a more advanced stage, but that new information gives patients the option to choose palliative care. It isn't a good outcome, but it ensures futile treatments are abandoned, resources are conserved and the best treatment path is chosen for each individual. Every patient deserves to know the exact state of their cancer before they commit to harsh chemotherapy treatments or complicated surgeries.
Susan Martinuk is a medical research consultant, well-known columnist and author of The Use of Positron Emission Tomography (PET) in Cancer Care across Canada: Time for a National Strategy. The report, commissioned by Advanced Applied Physics Solutions, is available at www.triumf.ca